1. Specific aims The specific aims of the entire innate expansion project are: 1. To characterise the functional capacity of peripheral blood NK and DC subsets during the earliest phase of acute HIV infection (AMI), to gain insight into innate immune functions in the critical initial phase of infection, ii. To analyse the functional properties of peripheral blood NK and DC subsets in EU and UU individuals, to identify protective aspects of the functions/interaction of innate subsets associated with EU status. iii. To compare the capacity of peripheral blood mononuclear cells (PBMCs) from EU and UU individuals to support HIV infection in vitro, and investigate the mechanisms underlying relative resistance to infection.